Process and composition for rectification of curly hair



Patented July 27, 1937 UNITED STATES PROCESS AND COMPOSITION FORRECTIFI- OATION OF CURLY HAIR Julian Y. Malone, Joseph H. Carroll, andCharles R. McKee, Milwaukee, Wis., assignors to The Perwav Company,Milwaukee, Wis, a

tion of Wisconsin No Drawing.

3 Claims. This. invention deals with compositions and methods forremoving objectionably obdurate kinkiness or curliness from human hair.

duce it to an easily moidable state. The mineral binder, present inproportion sufficient to render the composition pastelike, serves topreserve the hair in straightened order produced by brushing or combinguntil the softening ingredients of the composition effectivelyde-elasticizes the hair so that the kinkiness or curliness thereof ismore or less completely removed and a practically straightened conditionproduced which, after removal of the composition, is preserved.Sometimes it is also desirable to include in the composition emollientssuch as glycerine, or tri,- ethanolamine, or other substituted amines,which will tend to adhere to the hair after the remainder of thecomposition is removed and prevent the hair from becoming dry.

The composition of this invention is an improvement upon compositionsheretofore employed for the purpose. Compositions known prior to thisinvention have been harsh and irritating and, in some cases, dangerouslyso. Previously known compositions of any merit which have actuallyproduced what might be called a permanent straightening of hair havedepended for their action upon very strong free alkalies. Thesealkalies, together with waxes and the like, when applied to the hairhave exerted a softening action. The amount of free alkali necessary toobtain this efiect has invariably exceeded a non-irritatingconcentration and the tendency has been to reduce the concentration ofalkali in order to avoid irritation, in which case the softening actionnecessary to obtain permanent straightening has been lost. In thecomposition of this invention, on the other hand, the principalsoftening agents are negative radicals and free alkali is neithernecessary nor desirable, although nonirritating amounts thereof may beemployed. The mineral binder employed with this invention provides thenecessary temporary retention of the hair, but at the same time, due tothe ease of wetting thereof by the softening solution, the latter has atall times free and complete access to all parts of the hair surface.

In preparing the composition of this invention corpora- ApplicationFebruary 19, 1934, Serial No. 711,988

a soiution of stannous chloride is prepared to which solution suflicientalkali hydroxide, such as sodium hydroxide, is added to convert all ofthe stannous chloride to sodium stannite. To this is then added sodiumpolysulfide solution prepared by digesting sulphur in alkali hydroxidesolution. To this alkali stannite, alkali sulfide composition is thenadded a small amount of zinc sulfate, suflicient to combine with allfree alkali present forming alkali zincate, which substance, although ofminor softening properties, itself substantially enhances the softeningproperties of the stannite and polysulfide. Inasmuch as the softeningproperty of tin is dependent upon the tin being present in a stannouscondition, there is added to the composition suflicient protectivereducing agent, such as sodium hyposuliite to prevent atmosphericoxidation of the tin. This solution containing the softening andprotective agents is then employed for the purpose of compounding apaste or cream in which the solution is the suspending fluid. Thepreferred manner of preparing such paste is to add alkali earth oxidesdirectly to the solution. The alkali earth oxide added to the solutionbecomes hydrated therein and after the elapse of sufli'pient time anextremely fine, smooth, colloidal, mineral binder is formed. Theresultis a paste or cream which is smooth and plastic to a high degree. It ispreferred that the proper amount of alkali earth oxide be added toproduce a cream just stiff enough to stand alone. This may be variedwidely, of course, depending upon the preference of the operator, but itshould be borne in mind that the paste should have sufficient mobilityso that it can be worked well into a head of hair and at the same timesuflicient stiffness to maintain the hair in straightened condition.

In employing the composition described above, the paste is workedthoroughly into the hair and the hair is then combed until it lies instraightenedorder. The composition is then permitted to dry or'partiallydry upon the hair. This occurs within an interval of about fifteenminutes to half an hour and may be hastened somewhat by the use of a hotair dryer. During this interval of drying, the hair is held instraightened order by the mineral binder and while so held the softeningsolution acts upon the hair substance itself. Large amounts of fluid aretaken up by the hair, causing it to swell. Under the action of thesoftening agent the cement substance between hair cells is softened andthis allows the cells to shift their relative position so that when thehair again hardens the new position is assumed. The elasticity of thehair returns as shown by its assuming the straight position after beingbent, just as the hair prior to any treatment assumes the kinky positionafter being held straight. At the completion of the drying interval thedried material is preferably rinsed out with clear water. The hair isthen combed to proper configuration and dried. The hair so straightenedcan also be shampooed with soap to remove the composition, if desired,without danger of recurrence of the kinky state, but the rinsing withclear water is more effective. After the hair has been so treated thenew configuration of the hair will remain without reversion untilreplaced by new growth.

A useful addition to the paste as prepared above is a small amount ofwater-soluble emollient, such as glycerine or triethanolamine, or othersubstituted amines. When an emollient is employed the hair may bedressed and handled with greater facility after treatment; there is lesstendency on the part of the hair to become excessively dry; and thestraightening effect is somewhat improved. The emollient is alsobeneficial in its effect upon the paste, imparting a certain lubricitythereto which makes the paste easier to comb into the hair. Thefollowing directions for compounding may sometimes be employed:

Eight parts by weight of sodium hydroxide are dissolved in twelve partsby weight of water. To this is added six parts by weight of sodiumpolysulfide solution, formed by digesting sulphur in a forty percentsolution of sodium hydroxide. To this is then added two parts by weightof stannous chloride contained in twenty-five parts by weight of water.There is then added two parts by weight of zinc sulphate dissolved intwentyfive parts by weight of water, and finally four parts by weight ofsodium hyposulfite dissolved in sixteen parts by weight of water isadded. A small amount of undissolved solids may remain and the solutionas above prepared may be filtered to remove the solids. To about twoparts by weight of the above solution is then added approximately onepart by weight of MgO. After the elapse of a period of time this mixturesets into a thick paste. This thick paste is then thoroughly stirredwhile adding to about eighty-five parts by weight thereof approximatelyfive parts of triethanolamine and four parts of glycerine. The paste isnow in completed condition, but if through slight departures from theexact proportions or for other reasons the composition is not of exactlythe desired consistency, this may be adjusted to either thicken it orthin it, as necessary, by the addition, respectively, of small amountsof MgO or small amounts of additional solution as first prepared.

In compounding the above composition the quantity of stannous chloridemay be varied between relatively wide limits without producing anentirely inoperative composition. Some degree of operativeness will befound in the range between one-half to ten parts by weight of stannouschloride. In the case of zinc sulphate, this is also true inapproximately the same range. The quantity of sodium hydroxide employedis related to the quantity of zinc and tin present. This can rangebetween two to fifteen parts by weight.. The quantity of hyposulfite mayrange between three parts by weight and thirty parts by weight. Thequantity of polysulfide solution employed may also be varied widely fromtwo parts to twenty parts by weight. The quantity of magnesium oxideemployed is entirely dependent upon the consistency of cream desired.This will be found to lie within the approximate neighborhood ofthree-fourths to two parts by weight of magnesium oxide to two parts byweight of solution, but variation therefrom may be resorted to if adifferent consistency is desired. The quantity or presence of theemollient is optional, the quantity shown being representative of onlyone functioning proportion within a wide range. Any quantity oftriethanolamine from one-half to fifteen per cent is useful and thequantity of glycerine can vary within one-half to ten per cent.

Due to the chemical reactions which take place in compounding thecomposition under the above directions, a composition is formed whichWill contain from three-tenths to eight per cent of stannous tincompounds, three-tenths to eight per cent of sodium zincate, two tofifteen per cent of sodium hypo-sulfite, and one-half to eighteen percent of sodium polysulfide in addition to twenty-five to fifty per centof magnesium hydrate and two to fifteen per cent of triethanolamine andone-half to ten per cent of glycerine, together with some neutral salts,such as sodium chloride and sulfate, and possibly some free alkali.

In the above composition the recognized equivalents of sodium, such aspotassium, may be substituted. The sodium hypo-sulfite can be replacedwith any other nonpoisonous, non-irritating, mild, reducing agent ofsufiicient reducing activity to preferentially accept oxidation in thepresence of stannous tin. Such reducing agents will hereinafter bereferred to as protective agents. Examples of these are hydroquinone andNa2S.

The hydrated alkaline earth oxide which forms the mineral binder in thecomposition may be replaced in whole or in part by any well-knownequivalent, such as calcium hydrate, and also, at times, as well bycomplex silicates with or without alumina such as kaolin, bentonite, orother colloidal mineral. Herein the term mineral binder will be employedto mean any of the above substances in a highly divided, suspendedstate.

What we claim as our invention is:

1. A composition of matter for the straightening of hair comprisingthree-tenths to eight per cent of basic compounds of stannous tin,threetenths to eight per cent of sodium zincate, two to fifteen per centof sodium hyposulfite, one-half to eighteen per cent of sodiumpolysulfide, and twenty-five to fifty per cent of mineral binder.

2. A composition of matter for the straightening of hair comprising asuspension consisting of solid suspended matter and liquid, said liquidcontaining in the presence of hydroxyl ions and magnesium ions anon-depilating concentration of tin in stannous form as stannite and asstannous hydroxide, alkali polysulfide and alkali zincate, and thesuspended matter consists of highly divided mineral binder.

3. The method of straightening obdurately curly hair which consists inapplying to the hair a paste consisting in a mineral binder suspended ina softening solution containing from .3 to 8% of basic compound ofstannous tin, to 18% of sodium polysulfide, and free hydroxylmechanically extending the hair for retention in the extended state bythe binder while permitting softening solution to remove the elastictendency of the hair which would return the hair to curly condition,allowing the hair and applied composition to dry, and then removing thedried composition from the hair.

JULIAN Y. MALONE. JOSEPH H. CARROLL. CHARLES R. McKEE.

